From the author of

From the author of

The Many Faces of FireWire

By Scott Smith, author of FireWire Filmmaking

If you thought FireWire was merely a thin cable technology that did little
more than connect a camcorder to a computer, you're in for a few big surprises.
As of this writing, you can connect more than 1,000 devices via FireWire--computers,
laptops, video decks, still cameras, audio mixers, hubs, removable drives, DAT
recorders, and CD/DVD writers--to both professional- and consumer-level workstations.
And according to industry estimates, more than 200 million FireWire-equipped
products will have shipped by the year 2003. Although many of you may be familiar
with FireWire as a simple interface standard, there's some remarkable aspects
to this technology you might have missed.

Target Disk Mode

Stop-Motion Animation

Using Your Camcorder for TV Previews

FireWire Networking

1394b: The Next Generation

Target Disk Mode

One of the easiest ways to connect two FireWire computers and share files
is with a simple system configuration called target disk mode. This feature
is available only on Macintosh computers, but target disk mode theoretically
allows any computer with a FireWire port (the target computer) to be used as
an external hard disk. The target computer appears as a hard disk icon on the
desktop of the other machine--the host computer. For example, you could use
this feature to mount your PowerBook G3 on your G4 workstation as an additional
volume--like a portable hard disk--that can be accessed with full read/write
permission, just like any other storage device. Target disk mode works on any
FireWire-equipped PowerBook, iBook, Power Mac G4, G4 Cube, or iMac with Firmware
version 2.4, FireWire 2.3.3 drivers, and Mac OS 8.6 or later.

To successfully execute this operation, first be sure that your target computer
is shut down and that you've removed all other FireWire devices from both computers
prior to activating target disk mode. The host computer does not need to be
powered down, but you must connect the two computers with a 6-pin-to-6-pin cable
before starting. Apple also recommends that you connect the computers to AC
power.

Figure 1 A quick way to connect two Macintosh computers is by using
target disk mode--a feature of the Mac OS that lets a host computer mount
the internal hard drive of another FireWire computer simply by using a six-pin
cable.

As you boot up the target computer, immediately hold down the T key and
keep it down until the monitor displays the FireWire logo. Once the target computer
is up and running, its internal hard disk will appear as an icon on the Finder
desktop of the host computer. Now, you're ready to copy files to or from that
volume. Note: The host computer cannot access peripherals attached to a target
computer, only the internal hard drive.

When you've finished transferring files, you can simply drag the target computer's
icon to the Trash (or select Put Away from the File menu) and disconnect the
6-pin FireWire cable. Then you can press the target computer's power button
to turn it off. Don't attempt to reconnect any FireWire devices until after
you have disconnected the two computers from each other or have stopped using
target disk mode. If you unplug the target computer and then try to reconnect
it to the host, you may find the hard disk icon does not appear on the host
desktop. In this case, just check the cable connections and restart the host
computer.

Target disk mode isn't a true networking configuration (only one computer
is fully operational), but it's an incredibly handy way to quickly connect to
another computer and transfer files between internal hard disks. For Macintosh
users, target disk mode can be an indispensable tool in the moviemaking process.

Stop-Motion Animation

Among the first special effects techniques ever invented for the cinema, stop-motion
photography is a unique discipline that brings everyday objects to life by changing
the position of elements over a period of time. It's a painstaking effort, but
thankfully, FireWire has breathed new life into older stop-motion methods. For
example, you can now connect a DV camcorder directly to the FireWire port on
your computer and judiciously pick frames of video to import into your moviemaking
applications. As tired a phrase as it is, it's truly a revolutionary advancement.

New video frame-grabber software, specifically a shareware program called
FrameThief, can capture frames one at a time from almost any FireWire
webcam or camcorder. FireWire-equipped digital still cameras also work with
FrameThief, which imports pictures immediately and lets you review them in loop
cycles so you can instantly reject poor shots for better images. Previously,
animators had to guess if the film they shot had recorded the movement accurately.
Today, they can preview each frame and make subtle adjustments before capturing
the final image. You can download a free copy of FrameThief at www.framethief.com or use the version on
the DVD that's included with FireWire Filmmaking.

Figure 2FireWire frame grabber FrameThief is a video frame
grabber for stop-motion animators working on the Macintosh platform. Offering
a rich tool set for high-quality animation, FrameThief is compatible with nearly
all FireWire capture devices--from Webcams to digital still cameras and DV camcorders.
The program is based on a plug-in architecture that supports higher-end cameras
to produce HDTV or film-quality animations on a relatively small budget.

A word of warning: If you are using a digital camcorder, make sure you lock
the automatic exposure and manual white balance settings to prevent the camera
from making adjustments that can change the lighting and introduce tiny fluctuations
from frame to frame. Stop-motion relies heavily on persistence of vision to
create the illusion of movement, so any changes in the variables of your subject,
the set, the lighting, or the camera, will reveal shifting details in the final
sequence and spoil the magic. The automatic features of a DV camcorder can be
detrimental to this process.